1. Field of the Invention
The present invention relates to a method of constructing a replication environment in which a copy pair of a volume used by a group constituted by a plurality of applications is created in a storage system including a host computer, a storage apparatus, and a management computer; and to the storage system.
2. Description of the Related Art
Along with a wide spread of information systems, an amount of data handled by computing systems has been increased explosively. Importance of the handled data has also grown drastically. A high-level reliability in protecting such data has been required. Thus, a system of disaster recovery (DR) which can protect data from a logic failure (system failure) and a physical disaster has increasingly become important.
In the DR system, data can be duplicated by storing data outputted from a host computer which performs a task, not only in a volume in a storage apparatus directly connected to the host computer but also in a volume of another storage apparatus.
Typically, so-called local copy and remote copy are used in an information system which requires a high-level reliability. The local copy refers to a copying in which a data in a volume in a storage apparatus is copied in another volume of the same storage apparatus. The remote copy refers to a copying in which a data in a volume in a storage apparatus is copied in a volume in another storage apparatus. The local copy and the remote copy are collectively referred to as a replication. With a technique of the replication, if a volume has any trouble and cannot perform its operations, another volume can take over them using a duplicated data stored therein. Two volumes as a copy source and a copy destination in a replication relationship are collectively called a copy pair.
A replication is typically performed by selecting a volume used by an application desired to be copied, as a copy source, and selecting a volume having a free space sufficient to newly create a copy from the copy source, as a copy destination. This operation creates a configuration definition of a copy pair. A remote copy is performed by, as a preliminary operation, executing an initial copy based on information on the copy pair configuration definition prepared as described above. The initial copy means a copying of all data in the copy source volume into the copy destination volume. After executing the initial copy, an update copy is performed to the copy destination volume each time the host computer provides write data to the copy source volume. If a storage system as a copy source has any trouble, a task in the copy source volume can be restored using the copy destination volume in a storage system as a copy destination.
Japanese Laid-Open Patent Application, Publication No. 2005-11311 discloses a technique of creating a copy pair configuration definition by specifying an application as a copy source, in a storage system including a plurality of host computers and a plurality of storage apparatuses.
In Japanese Laid-Open Patent Application, Publication No. 2005-11311, a resource at a copy destination (a secondary computer resource) is selected based on at least a set of user-specified policy. The policy used herein includes characteristics (for example, reliability) of a secondary computer resource and a cost thereof. Nevertheless, such a selection does not give sufficient consideration to a task executed in the host computer.
A problem in constructing a DR system is an environment construction of a replication by a task as a unit. This is because, if a task is constituted by a group configured by a plurality of applications, protection of one or more specific applications alone is not sufficient to carry on the task. Such a task may be constituted by a plurality of associated applications, or a specific application in the task may have a cluster configuration.
The present invention has been made in an attempt to solve the aforementioned problems. The present invention provides a method of constructing a replication environment in which a copy pair of a volume used by a group constituted by a plurality of applications in a storage system is created, and the storage system.